Clutch actuating mechanism



June 8, 1948. w. v. THELANDE-R 2,442,787

CLUTCH ACTUATING MECHANISM Original Filed Dec. 12, 1941 2 Sheets-Sheet lPatented June 8, 1948 OFFICE 2,442.78: cLU'rcn ACTUATING MECHANISM W.Vincent Thelandcr, Auburn.

Toledo.

Dana

ti of pora on Ind, atria-nor to Ohio, a corporation Original applicationDecember 12. 1941, Serial No.

422,614. Divided 9 Claims.

This application is a division of my copending application Serial No.422,614, filed December 12, 1941, now Patent #2379924, June 26, 1945.

This invention relates to friction clutches, and has particularreference to an improved clutch actuating mechanism which althoughespecially designed for use with two-way clutches having two disksadapted to have drive transmitted thereto selectively is alsoadapted'for use with single disk clutches.

parts subject to heating in the operation of the clutch, the said springmeans cooperating with clutch actuating levers so as to apply springpressure to the pressure plate, said spring means affordingsubstantially constant pressure on the pressure plate when the clutch isengaged regardless of wear on the clutch disk facings and permittingmovement past dead-center of the toggle linkage operating the actuatinglevers, whereby the clutch is automatically held in engaged positionunder spring pressure until manually released.

The invention is illustrated in the accompanying drawings, in which-Figure 1 is a longitudinal section through a clutch embodying the novelclutch actuating mechanism of my invention, half of the section beingomitted to conserve space and permit showing the parts on a. largerscale;

Figs. 2 and 3 are fragmentary sectional details showing other portionsof the .clutch, Fig. 3 being a sectional detail on the line 3-3 of Fig.2, and

Fig. 4 is a section similar to Fig. 1 illustrating another clutchembodying a clutch actuating mechanism of modified or alternativeconstruction. I

Similar reference numerals are applied to corresponding parts throughoutthe views.

Referring first toFigs. 1 to 3, the reference numeral l designates theflywheel of an engine, and ii the back plate thereon. i2 is a drivenshaft extending rearwardly from the flywheel adapted for directconnection with the propeller shaft or to be extended into the front endof the gear box of a transmission, and i3 is a quill surrounding theshaft and serving as an auxiliary driven member, the shaft l2 being forhigh ratio drive and the quill l3 for low ratio drive, as will soonappear. The shaft l2 has the usual pilot bearing i4 supporting the frontend thereof at the center of the flywheel it. IS and it are and 1944,Serial No. 543,341

this application July 3,

2 clutch disks, the disk l5 having its center hub l'l' splined on thefront end of the shaft H to transmit drive from the flywheel to theshaft when the disk 15 is engaged, and the disk It having its hub l8splined on the front end of the quill l3 to transmit drive from theflywheel to the quill when the disk i6 is engaged. At iii are shown theusual pads or facings on the clutch disks, and at 20 is indicated apressure plate between the two disks, adapted when moved forwardly toengage disk IS with the driving face 2i on the back of the flywheel andthe companion driving face 22 on the front of the pressure plate. Thepressure plate is also movable rearwardly for engagement with disk IE tocause engagement thereof with the driving face 23 on the back plate Hand the companion driving face 24 on the back of the pressure plate. Thelatter is suitably cast like the flywheel and back plate and the faces2i-24 are accurately machined on these cast parts to cause smooth clutchengagement. The back plate is suitably bolted to the flywheel by meansof its marginal flange portion 25 and has a plurality of drive lugs 26cast integral therewith and projecting forwardly therefrom incircumferentially spaced relation for slidable driving engagement inradial notches 21 in the periphery of the pressure plate 20. Hardenedwear plates 28 are riveted onto opposite sides of the lugs 26, as shown,to minimize wear. The pressure plate has a plurality of posts 29 rigidlyattached to and projecting rearwardly from the peripheral portionthereof in circumferentially spaced relation. These posts extend freelythrough holes 30 provided in the :back plate, and have reduced .rear endportions 3| for slidably mounting stamped sheet metal rings 32 and 33,through which the reduced end portions 3| of the posts project, asshown. The reduced and portions 3! of the posts also serve as supportsfor coiled compression springs 34 which surround these end portions 3!and have engagement at their opposite ends with the rings 32 and 33.Additional coiled compression springs 35 are interposed between therings and supported at cylindrical bosses 36 and 37 struck inwardly fromthe rings. The springs 34 and 35 are all preloaded when nuts 38 threadedon the further reduced ends of the posts 29 are tightened against theshoulders 39. The rings 32 and 33 have annular flanges 40 and M on theirinner peripheries in concentric relation to the ringsand back plate andpressure plate, and these flanges are in axially spaced relation so thatthe clutch actuating levers 42 and 43 for selective engagement of theclutch their opposite ends by hollowpression of the springs in either ofthe two operative pofltions of the pressure plate can further compressthe springs to have the clutch engaged under increased spring pressurein either of the two aforesaid positions of the pressure plate. Thelevers 42 and 43, of which there will preferably be six sets in equallycircumferentially spaced relation with respect to the back plate, aremounted in paired relation, as shown in Fig. 2, between lugs 44 oncommon pivot pins 45, each of the levers 42 being bifurcated, asindicated, to provide two bearings 45 to receive therebetween the singlebearing 41 of the associated lever 43. Fingers 43 on the levers 42 and43 project radially outwardly and have rounded outer end portions forsliding engagement with the flanges 45 and 4|, as clearly appears inFig. 1, these fingers moving in an endwise direction relative to theposts 25 in the oscillatory movement 'of the levers 42 and 43 to movethe rings 32 and 33 forwardly or rearwardly depending upon the directionof movement of the throw-out collar 55. Toggle links 49 and 5|lare 43remote from the pivot pin 45, as at 5| and 52', and these links arepivotally connected, as at 53 and 54, to themanually reciprocablethrow-out collar 55. There are, of course, toggle links The pivots 53and 54 are than the pivots 5| and 52 so that when the collar 55 is movedforwardly from the neutral position shown the links 43 move wisedirection toward operative position as the pivots 53 move toward a planethrough the pivots 5| normal to the axis of rotation, the levers 43meanwhile being retracted from operative relationship to the flange 4|by the links 50. On the other hand in the rearward movement of thecollar 55 from the neutral position shown, the links 50 move the levers43 in a counterclockwise direction toward operative position as thepivots 54 move toward a plane through the pivots 52 normal to the axisof rotation, the levers 42 meanwhile being retracted from operativeposition to the flange 40 by the links initial movement of the levers 42toward operative position, the pressure plate 25 is brought intoengagement with the clutch disk i5, and in the further movement the ring32 is moved toward the ring 33 to compress the springs 34 and 35,thereby engaging the clutch disk i5 under a pressure substantially abovethe preload pressure of the springs. In the initial movement of thelevers 43 toward operative position, the pressure plate 25 engage theclutch disk l5, and thereafter in the further movement of the levers thering 33 is moved toward the ring 32 so as to further compress thesprings 34 and 35 and engage the clutch disk under a pressuresubstantially above the preload pressure. The present clutch is of the"over-center type and provision is accordingly made for movement of thethrowout collar 55 past the dead center positions, both in forwardmovement from the neutral position and in rearward movement from theneutral position. Thus, for example, in the forward movement of thecollar 55 there is maximum comwhen the pivots 53 are in dead centerrelationship to the pivots 5|, namely, when said pivots are in the sameplane with the pivots 5| normal to the axis of rotation, and at thatpoint the lug 55 on the collar 55 is in closely spaced relation to theback face 51 on the back plate and is arranged to be broughtintoengagement with said face by the slight amount of the levers 42 in aclock 49. In the pivotally connected to the ends of the levers 42 and Ias many sets of 45 and 5|] as there arelevers 42 and 43.

much closer together 'ward position so that the clutch is not additionalforward movement or the cohar necessary. the tonic links 45 in that sliht additional movement being moved "over center. There is, therefore, noappreciable reduction in spring pressure in the movement past center,but the spring pressure is made effective to hold the throw-out collarresiliently in the extreme forapt to be accidentally disengaged.Generally speaking, the same operation occurs in the rearward movementof the collar 55, the springs having maximum compression when the pivots54 are in dead center relationship to the pivots 52, and the lug 55being in closely spaced relation under those conditions to the frontface 55 of a ring 55 carried on the back plate. Blight further rearwardmovement of the collar 55 under those conditions brings the lug 55 intoengagement with the ring 53 and the toggle links 55 and is thereby movedover center. Here again it is clear that there .of'screws 55 and. asindicated at 5|, is cut away on the inner peripheray to provide therequired operating clearance for the links 55. When the collar 55 is inthe neutral position shown, spring pressed plungers 52 and 53 mounted inthe peripheral portion of the pressure plate 25 are effective to holdthe collar yieldingly in that position so as toprevent accidentalengagement of the clutch, the plungers 52 serving yieldingly to preventrearward movement of the pressure plate by light frictional .contactwith the inner face 23 of the back plate, and the plungers 53 servinglikewise toprevent forward movement of the pressure plate by lightfrictional contact with the back face 2| of the flywheel. There arepreferably three plungers 52 in equally circumferentially spacedrelation relative to the pressure plate 20 and three plungers 53 inequally circumferentially spaced relation relative to the pressure plate20. These plungers are preferably disposed in pairs on opposite sides ofthe notches 21 in the pressure plate, as illustrated in Fig. 2, therebeing preferably three drive lugs 25 on the back plate to cooperate withthree equally circumferentially spaced notches 21 in the periphery ofthe pressure plate. Each of the plungers 52 and 53 has a loose workingfit in a bore 54, as shown in Fig. 2, and has a reduced stem portion 55reciprocable freely in a hole 55 communicating with the bore. A lightcoiled compression spring 51 surrounds the'stem 55 in the bore 54 andacts to hold the plunger normally in the extended position. A washer 55riveted on the outer end of the stem 55 limits the outward movement ofthe plunger. Y

It should be understood that although I have shown a clutch having twodisks l5 and i5 adapted to be driven selectively, the clutch actuatingmechanism of my invention is also applicable to a clutch having only theone disk I5. Forward movement of the throw-out collar "by means of amanually operable clutch pedal or lever (not shown) causes engagement ofthe disk |5. 0n the other hand, when the collar 55 is moved rearwardlythe disk I5 is engaged. The springs 34 and 35 in addition to providingresilient engagement in either a single disk or two disk clutch so thatclose adjustment is not recenter type, provide substantially constantpressure and accordingly non-slipping engagement regardless of the usualwear on the clutch facings Is. In addition, the springs act to hold thethrow-out collar 55 resiliently in either engaged position, thusavoiding likelihood of accidental disengagement of the clutch. Theplungers 62 and 63 insure prompt disengagement oi the pressure platefrom the clutch disks when the throwout collar 55 is moved to neutralposition for disengagement of the clutch, and these plungers hold thepressure plate yieldingly in the mid-position shown in Figs. 1 and 2 outof engagement with both disks so that there is no likelihood ofaccldental engagement of the clutch.

The clutch shown in Fig. 4 is similar to that just described, and inthis clutch the parts that correspond to parts in the other clutch havebeen numbered correspondingly, using prime numbers. The posts 15 rigidwith and projecting rearwardly from the pressure plate 20' have flatfaces 16 on the opposite sides thereof and have a close working fit incorrespondingly shaped holes ll provided in the back plate H to providea sliding driving connection between the pressure plate and back plate.The posts '55, of which there are preferably six in equallycircumferentially spaced relation relative to the back plate, havereduced cylindrical end portions it, which are further reduced at theirextremities l9 and threaded to receive nuts 36 to hold the cast rings32' and 33' in place on the posts with coiled compression springs 34'compressed therebetween, similarly as in the other clutch. When thewashers under the nuts 80 are tightened against the shoulders 8|, apredetermined preload pressure is established. Hardened steel stirrups82 and 83 are set in the cast rings 32 and 33', respectively, forcooperation with actuating forks 8d pivoted, as at 85, between lugs ddcast integral with and projectlng rearwardly from the back plate ii. Thefingers 53' on each fork are engaged in the associated stirrups 82 and83 so that when the fork 8 3 is oscillated in one direction or theother, the pressure plate 23 is moved correspondingly and the springs34% and such other springs as may be provided between the rings 32' and33', like the springs 35 in Fig. l, are compressed beyond the preloadpressure after the pressure plate has engaged the clutch disk lb or it,as the case may be. The fork 8% is arranged to be oscillated in eitherdirection from the central neutral position shown by reciprocation ofthe throw-out collar 55 through the lost motion link connections shown,links 35 and ti being pivotally connected at one end on a common pivotpin as to the throw-out collar and having pin and slot connections attheir other ends with the fork at, as indicated at 89 and 88. Thepressure plate til, it will be understood, is equipped with springpressed plungers like those shown in the other clutch, so as to hold thepressure plate yieldingly in the middle neutral position and avoidlikelihood of accidental engagement of the clutch. The forward end 9i ofthe throw-out collar is arranged to engage the back face 92 of the backplate when the throw out collar is moved to an extreme forward positionwhere the pivots so are moved slightly past dead center relationship tothe pivots 89, similarly as in the over-center movement described in theother clutch. Similar provision may be made for limiting movement of thethrow-out collar past the dead center position in its rearward movement6 as described in the other clutch. In that way the clutch is heldengaged resiliently and there is avoided likelihood of accidentaldisengagement, and, of course, the springs 34' and such other springs asmay be provided between the rings 32' and 33 aflord substantiallyconstant engaging pressure to compensate for wear in the operation ofthe clutch, similarly as in the other clutch. The operation of thisclutch is so closely similar to the operation of the other clutch nofurther description is considered necessary.

It is believed the foregoing description conveys a good understanding ofthe objects and advantages of my invention. The appended claims havebeen drawn to cover all legitimate modifications and adaptations.

I claim:

1. In a friction clutch, comprising a flywheel having a back plate, aclutch disk, a pressure plate for frictionally engaging the clutch disk,supports extending from the pressure plate to a plane behind the backplate, springs and spring caging ring means therefor slidably mounted onsaid supports, and over-center clutch actuating lever means pivotallymounted on the back plate and operatively associated with said ringmeans to move the pressure plate to engaged position and engage theclutch resiliently under pressure of said springs, the clutch beinglocked resiliently by said springs in engaged position when said levermeans has been moved past a. predetermined dead center position.

2. In a friction clutch, comprising a flywheel having a back plate, aclutch disk, a pressure plate for frictionally engaging the clutch disk,supports extending from the pressure plate to a plane behind the backplate, a plurality of springs, cage means for said springs movablymounted on said supports and supporting said springs thereon incircumferentially spaced relation, a throw-out member reciprocabletoward and away from the back plate, and over-center lever means pivotedrelative to the back plate and operatively connecting said throw-outmember and said cage means to move the latter so as to engage the clutchand transmit engaging pressure through said springs to the pressureplate and lock the clutch in engaged position upon movement of saidlever means past a dead-center position.

3. In a friction clutch comprising a fiy-wheel having a back plate, aclutch disk, a pressure plate for rrictionally engaging the clutch diskhaving supports thereon for spring means extending to a plane behind theback plate, spring means caged in preloaded condition on the supports,and over-center type positive acting mechanical clutch actuating meansfor moving said supports and the pressure plate to engage the clutchdisk resiliently by compression of the spring means above the preloadpressure and lock the clutch resiliently in engaged condition under thesame spring pressure.

el. In a friction clutch comprising a fiy-wheel having a back plate, aclutch disk, a pressure plate for irlctionally engaging the clutch disk,a pair of ring members in concentric relation to said plates and guidedfor a limited axial movement with respect to the pressure plate andadaptedto hold and compress a compressible resilient means caged on saidring members, a throw-out member reciprocable toward and away from theback plate, and over-center lever means operatively connecting saidthrow-out member and said members soas to engage the clutch resilientlyand lock the clutch in engaged position.-

5. In a friction clutch comprising a fly-wheel having a back plate, aclutch disk, 0. pressure plate for frictionally engaging the clutch diskto the pressure plate and adapted-to support 1 springs, a plurality ofsprings supported on said rings in circumierentially spaced relation,; athrow-out member reciprocable toward and away from the back plate, andover-center lever means providing a lost motion operating-connectionbetween said throw-out member and said rings to permit resilientengagement of the clutch and also permit locking of the clutchin-engaged position.

6. In a friction clutch. comprising a fly-wheel having a back plate, aclutch disk, 9. pressure plate for frictionally engaging the clutch diskhaving ring supporting means thereon, a pair of ring members supportedby said means on the pressure plate in concentric relation thereto andguided on said supporting means for a limited axial movement withrespect to the pressure plate and adapted to support springs, aplurality of springs supported in circumferentially spaced relation tosaid rings, and lever means mounted for pivotal movement relative to theback plate and operatively engaging the rings to move the pressure platerelative to the back plate to engage the clutch disk and load theaforesaid springs so as to engage the clutch resiliently.

'7. In a friction clutch comprising a fly-wheel l having a back plate, aclutch disk, a pressure plate for frictionally engaging the clutch diskhavin ring supporting means thereon, a pair of rings members supportedby said means on the pres- -sure plate in concentric relation theretoand guided on said supporting means for a limited axial movement withrespect to the pressure plate.

and adapted to support springs, a plurality of springs supported incircumferentlally spaced relation to said rings, positive acting levermeans mounted for pivotal movement relative to the position to move saidlever means to an extreme position in which the clutch is enga edresiliently and locked in such condition so long as said throwout memberis not returned to neutral position.

8. Im a friction clutch comprising a fly-wheel having a back plate, aclutch disk, a pressure plate for frietionally engaging the clutch diskhaving ring supporting means thereon. a pair of ring members supportedby said means on the pressure plate in concentric relation thereto andguided on said supporting means for a limited axial movement withrespect to the pressure plate and adapted to support springs, aplurality of springs supported in circumferentially spaced relation tosaid rings, positive acting lever means mounted for'pivotal movementrelative to the back plate and operatively engaging said rings to movethe pressure plate relative to the back plate to engage the clutch diskand compress the aforesaid springs to engage the clutch resiliently, athrow-out member guided for movement toward and away from the backplate, and means providing a lost motion operating connection betweensaid throw-out memberand said lever means.

9. In a friction clutch comprising a flywheel having a back plate, aclutch disk, a pressure plate for frictionally engaging the clutch disk-havingrearward projections rigid therewith extending to a plane behindthe back plate, spring means caged incompressed condition on said pro-:Iections behind and in spaced relation to the back plate, and positiveacting mechanical clutch actuating, means pivoted with respect to theback plate back plate and operatively engaging said rings to move thepressure plate relative to the back plate to engage the clutch disk andcompress the aforesaid springs to engage the clutch resiliently, athrow-out member guided for movement toward and away from the backplate, and lever actuating means carried on said throw-out member andarranged upon movement thereof from a neutral and including portionsmovable endwise relative .to said projectionsto'move said spring meanstoward the back plate, whereby first to engage the clutch disk more orless positively 'and thereafter further compress said spring means sothat the final engagement is under increased spring pressure. 1

' W. VINCENT FI'HELANDER.

REFERENCES CITED s'rs'rns PATENTS Number Name Date 1,791,016 Sundh'Sept. 14, 1943 1,861,080' Chorlton -May 31, 1932 2,249,043 Root July 15,1941 2,251,367 Miller -Aug. 5, 1941 1 2,259,784 Spase Oct. 21, 19412,329,205 Knox Sept. 14, 1943

